Circuit interrupter



July 31, 1951 H. RAWLINS ETAL CIRCUIT INTERRUPTER 3 Sheets-Sheet 1 Original Filed Jan. 16, 1941 INVENTORS f/erfierzl Fab/Z1773 3 c/d/fles N 14 411469.

.WITNESSES:

ATTORNEY July 31, 1951 H. L. RAWLINS ET AL 2,562,391

CIRCUIT INTERRUFTER Original Filed Jan. 16, 1941 5 Sheets-Sheet 2 WITNESSES: INVENTORS 'fle'r'berzLiFauiz'nsi Jgwes /7. Wallace.

ATTORNEY July 31, 1951 H. 1.. RAWLINS HAL 2,562,391

CIRCUIT INTERRUPTER Original Filed Jan. 16, 1941 3 Sheets-Sheet 5 James /7. Wallace.

Patented July 31, 1951 CIRCUIT INTERBUPTER Herbert L. Rawlins, Pittsburgh, and James M. Wallace, Braddock, Pa., assignors to Westinghouse Electric Corporation, East Pittsburgh,

Pa., a corporation of Pennsylvania Original application January 16, 1941, Serial No. 374,685, now Patent No. 2,405,606, dated August 13, 1946. Divided and this application November 21, 1944, Serial No. 564,442

1 12 Claims.

This invention is a division of our copending application Serial No. 374,685 on Circuit Interrupters, filed January 16, 1941, which issued as Patent No. 2,405,606 issued August 13, 1946, and reissued as Reissue Patent No. 23,033 on August 31, 1948, and relates generally to circuit interrupters, and more particularly to circuit breakers and their operating mechanisms.

This invention is especially adapted for use in small reclosing circuit breakers wherein it has certain particular novel cooperation providing certain novel and useful results, hovewer it should be understood that many features of this invention are capable of use with other types of circuit breakers, and even with other types of apparatus.

Automatic reclosing circuit breakers of this type comprise electroresponsive means for causing separation of the breaker contacts to interrupt the circuit, with means for automatically reclosing the breaker contacts following a circuit interrupting operation, and integrating means operative to prevent reclosure of the breaker contacts in response to a predetermined number of closely successive circuit interruptin operations.

One object of this invention is to provide a novel arrangement of biasing means for automatically reclosing a breaker of the type described.

Another object of this invention is to provide novel manual control means for causing opening and closing of the breaker contacts, which control means permits automatic opening of the contacts even when the control is held at its closed circuit position.

Another object of this invention is to provide in an automatic reclosing circuit breaker of the type which is automatically prevented from reclosing in response to a predetermined number of closely successive circuit interrupting operations, novel manually operable means for opening and closing the breaker independent of the automatic opening means, with said manually operable means also being manually movable to render said automatic reclosure-preventing means inoperative following operation of said reclosure-presentin means, so that the breaker may reclose, and said manually operable means further being incapable of preventing automatic opening of said breaker even though held at its closed circuit position.

These and other objects of this invention will become more apparent upon consideration of a 2 thereof, when taken in connection with the attached drawings, in which Figure 1 is a substantially central, longitudinal sectional view of one form of a circuit interrupter embodying the features of this invention.

Fig. 2 is a view similar to Fig. l, but taken from the opposite side thereof and showing certain of the parts in elevation and with the outer casing removed.

Fig. 3 is a side elevational view of the mechanism shown in Figs. 1 and 2, with a portion of the supporting frame removed.

Fig. 4 is a view like Fig. 3, but illustrating the position of the parts with the breaker contacts locked open, and v Fig. 5 is a partial elevation view of the cover for the interrupter.

Referring to the drawings, the embodiment of the invention illustrated includes a circuit interrupter adapted to be contained in an insulating tubular casing 2, which may be of any desired insulating material, such as porcelain, glass, or the like. The casin 2, a shown in Fig. 1, has a closed bottom end portion and an open top. The open top is provided with an upper terminal cover assembly 4, and the closed bottom of the casing is provided with a lower terminal assembly 6. An intermediate portion of the casing has a substantially cylindrical outer wall portion 8, upon which is mounted a cushioning sleeve Ill of rubber, fiber or the like, and on opposite sides of which may be clamped supporting bracket halves l2 (only one of which is shown) as by bolts l3. The supporting bracket portions 12 are adapted to be extended at one end thereof to support the interrupter in an operative position.

The lower terminal assembly 6 is mounted at the closed bottom portion of the insulating casing 2 by means of a conducting bolt l8, extending through an aperture IS in the closed end of easin 2, and the bolt is provided with. an enlarged disc-like head portion 20 positioned within the casing. with packing material 22 interposed between the head 20 and the adjacent inner surface of the closed end of insulating casing 2. The packing material 22 may be of any desired packing material, preferably one which is resistant to oil, such, for example, as cork, fiber or a synthetic rubber. Bolt II has a bore l4 therethrough, the outer end of which is closed by a threaded plug it for the purpose of draining casing 2 when desired. The bolt ll detailed description of a preferred embodiment a is secured in position by a nut 24 drawn up on the bolt against a washer 26, positioned between the nut 24 and the outer wall at the closed end of casing 2. A terminal strap 23 having connector elements 31 thereon, may be also secured to the bolt l3 by means of a second nut 39, as shown.

The upper terminal assembly I is in the form of a cover forthe open end 01' the casing and, as will be hereinafter more fully explained, also acts to secure the support for the interrupter and operating mechanism in operative relation at the open end of the casing.

Referring to Figs. 3 and 4, it will be noted that the cover 32 is provided with a transversely extending hollow portion for the reception of certain parts of the circuit breaker operating mechanism, and the top wall of this hollow portion is provided with a threaded aperture for the reception of a screw threaded flller plug 34, so that the supply of arc extinguishing fluid within the casing 2 may be renewed when necessary. Cover 32 also includes a peripheral flange portion 36 adapted to seat on the upper end walls of casing 2, and this flange has at its outer edge a downwardly turned lip portion 33, to aid in properly positioning the cover on the open end of casing 2. Packing material 43 is interposed between the cover flange 36 and the open end of the casing, and this material is preferably similar to packin material 22 previously described. Cover 32 is secured to the casing 2 by means of a support 42. fixedly mounted on the outside of easing 2. Support 42 is in the former an annulus which is substantially channel-shaped in cross-section, with the channel facing the outer surface of casing 2. The annular support 32 is secured to casing 2 by cast metal or the like 44, which is poured in between the support 42 and the outer casing wall. so as to enter within the channel support 42 and between corrugations 46 provided on the outer surface of the casing to securely anchor the support 42 thereto. Cover 32 is preferably secured to support ring 42 by spaced bolts passin through integral outstanding ears (not shown) provided on the cover and supporting ring, respectively. The casing and its terminal assembly thus far described are substantially like that disclosed and claimed in the copending application of J. M. Wallace, Serial No. 345,051. flied July 12, 1940, and issued September 21, 1948 as Patent No. 2,449,867, assigned to the same assignee of this invention.

As stated above, cover 32 is adapted to secure a support for the interrupter and its operating mechanism in operative relation at the open end of casing 2. This support for the interrupter and its operating mechanism (as shown) includes an upper substantially rectangular open frame portion having top and bottom walls 32 and 56, respectively, and side walls 54. Depending from the bottom wall of the upper rectangular frame portion, are a pair of spaced, substantially parailelly extendin supporting plate members 33, for supporting the interrupting chamber 52 at the lower ends thereof. The upper rectangular supporting frame portion is provided adjacent the top wall 52 thereof, with oppositely positioned, outwardly extending supporting flanges 43, adapted to be positioned on topoi' the end wall of easing 2, and be secured in position by screwsllengagingflangesllandanintegral lip ll formed on cover 32.

The interrupting chamber 32. includes a tubular insulating chamber portion 64 formed of any desired insulating material such. for example, as

4 flber or the like, which is adapted to have one end thereof threadedly engaged with a threaded socket 53 formed integral with the lower ends of supporting plates 53. The upper wall of socket 63 is provided with a plurality of spaced outlet passages 66, which are controlled by a disc-like valve member 53 mounted within insulating tube 64, and which operates to control the outlet passages 63 in a manner to be hereinafter described. Insulating tube 64 of the interrupter chamber is provided at the other end thereof with an end cap I3, threadedly engaged with the lower end of the insulating tube to close the same. The cap III is provided with passages 12 -for the flow of fluid into arc chamber 62, and

these passages are controlled by a check valve plate I4 adapted to be seated over inlet passages 12, within are chamber 62. End cap 10 is also provided with a substantially centrally located threaded aperture for the reception of a threaded fixed contact I6.

A movable contact assembly is adapted to cooperate with fixed contact I6, and includes a relatively short contact rod 13 located within interrupting chamber 62, and having an enlarged contact portion 19 with a tapered outer end for engagement with fixed contact I6. Short contact rod 13 is adapted to have the upper end thereof, as viewed in the drawings, threaded into a bore provided centrally of an insulating contact supporting rod 30, which is slidably mounted in a central aperture provided in socket 6|. The lower end of insulating contact rod 83 is provided with a counter-bore 32 for receiving a coil compression spring 8|, adapted to be seated at the other end thereof on a liquid director member 36. The liquid director 33 is substantially circular in form and includes a base portion 88 havin a substantially central aperture for slidably mounting the director on short contact rod 13, for movement between enlarged portion "of the contact rod and the lower end of insulating contact rod 33. Coil spring 34 normally biases the liquid director 36 towards the enlarged end 13 oi. short contact rod 18. However, in the closed position of the contacts, as shown, for example, in Fig. 1. spring 34 will be compressed, so that the liquid director will be located adjacent to the lower end of insulating contact rod 33. The liquid director 36 is provided with passages therethrough for directing the liquid into the path of an arc drawn when the contacts separate, and these include an outlet 33 located adjacent the enlarged contact portion 19, and this opens into a divergent passage 92 in the director, which in turn communicates with a plurality of spaced inlet passages 94, into which liquid contained in the interrupter chamber 62 is adapted to flow when the liquid director is moved upwardly. In the closed position of the contacts, liquid director 36 is adapted to rest on a stop ring 96 secured between a shoulder 33 on end cap 13, and the lower end of insulating tube 64. Valve plate 63 at the upper end of interrupting chamber 62 is provided with an integral angular flange I30 adapted to form a substantially annular groove about the outer surface of insulating contact rod ill, for the reception of packing material I02 to frictionally assogiate valve plate 63 with insulating contact rod 0.

With the exception of contact supporting rod 33 being of insulating material, the interrupter structure described above is substantially the same as that described in J. M. Wallace Patent No. 2,352,048 on Circuit Interrupters, issued June 20, 1944, to the same assignee of this invention, and which was copending with the aforesaid application of which this is a division. Consequently, for a fuller understanding of the structure and operation of the interrupter, reference is hereby made to the above-mentioned patent. Briefly, the operation of the interrupter 62 is as follows: When contact supporting rod 80 is moved upwardly carrying with it contact rod I8 and contact portion I8, the liquid director 86 is held in engagement with stop ring 96, until the base 88 thereof is engaged by the enlarged contact portion 18, by the biasing action exerted by coil spring 84. However, as soon as the contacts separate an arc will be drawn therebetween causing vaporization of the arc extinguishing fluid which will build up pressure within the interrupting chamber 62. This pressure forces check valve plate I4 to seat on and close off inlet passages 12, and upward movement of contact rod 80 carries valve plate 88 into a closed position with respect to outlet passages 66, to thereby effectively seal the interrupting chamber 62 during the circuit interrupting operation. As soon as the enlarged contact portion I9 on contact support I8 engages wall 88 of the liquid director, the director is moved upwardly along with the contact, and liquid will flow through inlet passages 94 and be directed through outlet passage 90 which will now be positioned as shown in Fig. 4 of the drawings, to direct liquid through the arc path. This lost motion between the contact and liquid director, when the circuit is interrupted, permits easy initial opening movement of the contacts and allow sufficient pressure to build up within the interrupter chamber 62 to close the valve I4, and

permits the arc to reach an optimum length before subjecting the same to currents of are extinguishing liquid. It will be noted that the pressure built up within the interrupter chamber will also act on the relatively large contact supporting rod 80 to assist in moving contact I8 away from fixed contact I6, inasmuch as the supporting rod 00 fits in a piston-like manner in socket 60.

After the circuit is interrupted, the contacts may be reclosed and it will be apparent that as soon as contact supporting rod 80 moves downwardly, it will carry valve plate 68 with it into engagement with the upper edge of insulating tube 64, which is notched as at 6|, to permit free outlet of used fluid and any gases which may have been produced by the interrupting operation. At the same time, the head of liquid in insulating casing 2 will cause check valve plate I4 to rise and allow fresh fluid to enter inlet passages I2 to replace the used liquid.

Contactsupporting rod 00 is adapted to be actuated by an elongated actuating rod I04 threadedly engaged in a bore in the upper end of rod 80, and having the opposite end secured in a threaded socket in the lower end of a connecting rod I06. The connecting rod I06 has an enlarged portion forming a shoulder I24, and the enlarged portion is adapted to be slidably mounted in a closure plug IIB secured in upper wall 52 of the supporting frame. The upper end of connecting rod I06 is bifurcated for receiving the ends of a pair of toggle links 0 pivotally secured to connecting rod I08 as by a pivot pin I08. The

' toggle levers IIO are adapted to diverge and have their opposite ends slotted to receive fixed guide pins II2, respectively, mounted on integral supporting lug portions II4 formed on cover 32. A

coiled compression spring H6 is adapted to be coiled about each toggle lever IIO to react be tween the supporting pins H2 and a shoulder formed on each toggle lever IIO to normally bias actuating rod I04 in a direction to force contact portion I9 into engagement with fixed contact I6.

In order to separate the contacts, a solenoid coil I I8 is adapted to be mounted in the rectangular portion of the supporting frame, and the coil is provided with a core I20 adapted to be drawn up into a center bore in the coil. The solenoid core I20 is movably mounted on connecting rod I04, and is provided with a counter-bore portion I22 for receiving therein a coil spring I23. Preferably, the core plug H8 at the upper end of solenoid coil Ila is, like movable core I20, and sides 54 of the supporting frame, of a magnetic material, so as to form a closed magnetic path when plug H9 is engaged by movable core I20.

The solenod coil I I8 is adapted to be connected in series in the circuit through the interrupter. as will be hereinafter described, and upon the occurrence of overload conditions in the circuit, the solenoid coil will attract movable core I20, and move the same upwardly without moving actuating rod I00 or contact I9, until coil spring I23 engages the lower end I05 of connecting rod I06. From this point on, further movement upwardly of movable core I20 will cause compression of spring I23, until the upper end of the core engages shoulder I24 on connecting rod I06 to deliver an impact on connecting rod I06, to separate contact portions I9 and I6, notwithstanding any possible welding of the contacts together. This will cause contact I9 to move upwardly and it is carried for the completion of its stroke after solenoid core I20 engages plug core H9, by the force stored in coil spring I23. Coil spring I23 is preferably of such strength as to overcome the force exerted by toggle springs I I6 after a predetermined strain thereof. Moreover, it may be noted that the force exerted by toggle springs I I6 in a direction to cause engagement of contact portion I9 with fixed contact I6, will decrease -as the contact I9 moves upwardly, because of the toggle effect of levers IIO. Moreover, the opening movement of the contacts isiurther aided by the pressure which may be developed by the are formed when the contacts separate, acting to move contact I9 upwardly, as described above.

Movable solenoid core I20 is provided adjacent the lower end thereof with oppositely projecting pins I26 having enlarged outer ends for reception in guide slots I28, formed in supporting plates 58, to prevent rotation thereof about a longitudinal axis. A rack I3I is adapted to be pivotally mounted on one of the pins I26 for engagement, in one position of solenoid core I20, with a pinion I30 mounted on a shaft I34 extending between and rotatably mounted in the spaced frame members 58. A spring I32 is adapted to be coiled about guide pin I26, with one end thereof engaging movable core I20, and the other end thereof engageable with rack I3I, to normally urge the rack into engagement with pinion I30. It will be noted that the teeth on rack I3I are inclined downwardly so that in the upward motion of the rack with movable core I20, the teeth 'of the rack will slide freely over the teeth of pinion I30; but on downward motion of the rack the teeth will engage pinion I30 to rotate the same in a clockwise direction as viewed in Figs. 3 and 4. A relatively large gear I38 is also fixed to shaft I34, and this shaft, together with pinion I30 and gear I38, are biased in a counterclockwise direction by a spring I36 coiled about shaft I34, and having one end thereof engageable with the supporting frame, and the other end thereof engaging a pin I40 on gear I38. The pin I40 projecting from one side of gear I38 is adapted to control a trip controlling member in a manner to be hereinafter further specified.

A short stop lug I42 projects from the opposite side of gear I38 and is normally adapted to engage a lever I44 pivotally mounted on the supporting frame, as by the pivot pin I45, and engageable at the outer end thereof with shaft I34, so that, as viewed in Figs. 3 and 4, the stop pin I42, by its engagement with lever I44, limits movement of gear I28 in a counterclockwise direction under the influence of spring I35. A con trol lever I50 is preferably pivotally mounted as at I48, on one supporting plate 58, and is provided at one corner of the free end thereof with a curved catch I52, insulatingly secured to control lever I50 in any desired manner, and adapted to be engaged by an adjustable stop lug I54 mounted in the free end of a bimetal element I55. Bimetal element I55 is supported from the frame 58 by an angular bracket I58 and is of conventional construction, that is, it includes a pair of laminations of materials having different coefficients of expansion intimately secured together, wth the material having the larger coefficient of expansion comprising the lower lamination, so that upon being heated, the bimetal will deflect upwardly as viewed in the drawings.

It can be seen, therefore, that the lug I54, normally, as shown in Fig. 3, prevents counterclockwise rotation of control lever I50. Clockwise rotation of trip control lever I50 about its pivot I48, is limited by a laterally projecting stop lug I50 integral with the lever, and engageable with an edge of the adjacent supporting plate 58. At the other corner of the free end of control lever I50.

.there is pivotally mounted as at I52. a contact stop lever I54. This lever, at its upper portion, comprises a pair of legs pivoted on pivot pin I52, at opposite sides of control lever I50, and having laterally extending integral portions I53 connected at their outer ends by an integral stop portion I55, which is engageable with control lever I50 in the position of contact stop lever I54 shown in Fig. 4 of the drawings, to limit relative counterclockwise rotation thereof. One leg of contact stop lever I54, and control lever I50 are provided with lateral extensions I59 and HI, respectively, which are apertured so that the ends of a coiled tension spring I13 may be hooked into these extensions to bias contact stop lever I54, relative to control lever I50, in a counterclockwise direction about pivot point I52. One of the legs of contact stop lever I54 is extended, as shown at, I58, so as to be engageable by control pin I40 on gear I38, to normally maintain the contact stop lever in the position shown in Fig. 3 of the drawing, so that the stop portion I51 of the lever is maintained out of the path of movement of pin I on solenoid core I20. Gear I is adapted to drive a time delay means, comprising pinion I10 with which gear I meshes, gear I12 fixed for rotation with pinion I10, and pinion I14 adapted to mesh with gear I12 for driving a paddle wheel I15, positioned below the level of the arc extinguishing liquid within casing 2.

In the operation of the mechanism thus far described, it can be seen that when the contacts are opened by sufficient energization of solenoid coil II8 to draw movable core I20 upwardly into the coil, that even prior to movement of contact 19 by the solenoid, rack III will engage pinion I34, irrespective of the amount of travel of the contact necessary to interrupt the circuit. After interruption occurs, contact 18 is moved into engagement with fixed contact 15 by toggle springs I I5. This circuit closing operation will always cause rack I3l to rotate the time delay mechanism a predetermined amount, inasmuch as rack I3I is secured to solenoid core I20 and, therefore, its movement is independent of the amount of separating movement of the contact rod I04 as pointed out above. As the contacts are reclosed following an initial circuit interrupting operation, it will be observed that rack I3I will rotate gear I28 in a clockwise direction as viewed in Figs. 3 and 4 against the bias of spring I35, and this rotation will remove control pin I40 from contact stop lever I54 to permit this lever to be moved by spring I13 in a counterclockwise direction about pivot I52, to a position limited by connecting stop portion I55 and wherein the hook portion I51 of the lever is positioned at a point to intercept pin I25 on solenoid core I20, in the event a closely succeeding interrupting operation occurs. In the event the overload on the circuit has disappeared when the contacts are reclosed, gear I38 will be rotated in a counterclockwise direction by spring I35 slowly, since spring I35 must operate the time delay gearing and paddle wheel I15, until eventually control pin I40 re-engages portion I58 of contact stop lever I54 and moves it back to the position shown in Fig. 3 of the drawings. In this position, it is obvious that in the event an overload again occurs in the circuit, the contacts will be quickly separated by solenoid II8.

In the event, however, that upon reclosure after the first interrupting operation of the circuit breaker, the overload still exists on the circuit, solenoid coil II8 will immediately again lift movable core I20 upwardly, but its movement in this direction is now limited by hook portion I51 of contact stop lever I54, so that its movement will be halted before it is operative to raise contact 19. However, bimetal I55 is connected in series with solenoid coil I I5 in the circuit through the interrupter, as will be hereinafter pointed out, and alter a predetermined period of time the bimetal becomes heated by the overload current, and deflects to the position shown in Fig. 4, thus releasing catch I52 on control lever I50, so that this lever and stop lever I54 are now free to rotate as a unit about pivot I48 of lever I50, under the biasing force exerted by the solenoid pull through pin I25 on hook portion I51, which pull is exerted along a line offset with respect to pivot I48. This will free the pin I25 and permit the contacts to be opened in the manner previously described. After the circuit is interrupted the contacts will be reclosed by toggle springs II5, with the reclosure again being delayed by operation of the time delay mechanism by rack I3I. If the fault has been cleared after the second reclosure, bimetal I55 will gradually assume its normal position shown in Fig. 3 to engage catch I52 on trip control lever I50, and gear I38 will be eventually rotated to the position where control pin I40 removes stop portion I51 of lever I54 from the path of movement of solenoid pin I25, and stop pin I42 engages lever I44. It should be noted that control lever I58 is normally biased to the position shown in Figs. 3 and 4 of the drawings, that is, where stop lug I50 thereof engages the edge of adjacent support plate 58, by a spring I5I coiled about pivot I48 and engaging stop lug I40, and adjacent supporting plate 55.

' chamber.

If the fault has not been cleared by the time the second reclosure is made, the breaker contacts are again quickly separated by solenoid coil H8, and this time there is no time lag before the contacts separate because the bimetal has not had time to cool down, and consequently will remain in the position shown in Fig. 4 of the drawings; and, therefore, levers I64 and I50 may be rotated about pivot I48 by core pin I26 on the upward stroke of the solenoid core.

It can be seen from the foregoing that upon the occurrence of a continuing fault in the circult, the breaker contacts will be opened a plurality of times, with the first interrupting operation occurring substantially instantaneously in response to the occurrence of the fault, and the second closely succeeding interrupting operation will be delayed a predetermined time depending upon the time necessary to heat bimetal I56. Thereafter, any subsequent interruption will be relatively faster because the time delay means I56 being in a deflected position, will be inoperative to delay any such closely succeeding tripping operation. However, in the event that the fault clears after any reclosure of the breaker contacts, the mechanism will reset so that whenever a continuing fault occurs at a later time, the same sequence of circuit interrupting operations will occur, that is, a first quick opening of the contacts, a second time delay opening, and a quick opening thereafter. In connection with the intermediate time delay opening operation of the breaker contacts, it should be noted that the lost motion connection of the solenoid core with the movable contact, is utilized to prevent separation of the contacts for a time predetermined by bimetal I56. The above described arrangement of successive circuit interrupting operations has the advantage that better coordination with fuses can be obtained when the circuit being protected is subject to surges.

Normally inactive lockout means are provided in association with the mechanism described above adapted to be rendered active for locking the breaker contacts in open circuit position, in response to a predetermined number of closely successive interrupting operations. The lever I44 previously referred to, is adapted to control this lockout means, and it will be noted that this lever is normally biased into engagement with shaft I34, by a spring I18 coiled about pivot I46, and engageable with a lateral extension of the lever and with socket portion 60 of the interrupting Also pivotally mounted on the, lever pivot I46, is a lockout lever I80, which is biased with respect to lever I44, for movement in a counterclockwise direction, by spring I82 also coiled about pivot I46, and having opposite ends thereof engaging lever I44 and lookout lever I80. A lug I8I on lockout lever I80 is engageable with a lateral extension of lever I44 to limit movement of lockout lever I 80 relative to lever I44 under the influence of its spring I82.

As previously described, each time the interrupter contacts are closed, rack I3I is operative to rotate pinion I30 and, therefore, gear I38 in a clockwise direction as viewed in Figs. 3 and 4 of the drawings, and after the contacts are reclosed, the gear I38 is then slowly moved back to its normal position shown in Fig. 3. However, in the event of the occurrence of a continuing fault on the circuit, gear I38 will integrate closely successive circuit interrupting operations to finally, condition the lockout means described above to prevent further operation of the contacts. In the event of a continuing fault, before gear I38 is restored to its original position following a reclosure of the breaker contacts, these contacts are again reopened and gear I88 upon a second reclosure of the contacts is further advanced a predetermined distance in a clockwise direction by rack III, to bring stop lug I42 into engagement with the upper edge of lever I44 to move lockout lever I80 into engagement with rod I04 Just prior to engagement of the contacts. Now if the fault still remains, the contacts are instantaneously reopened before gear I88 can be moved any substantial distance from its thus advanced position in a counterclockwise direction, at this time shoulder I84 on rod I04 cams lockout'lever I80 outwardly in its upward movement so that when a third reclosure is attempted by toggle springs II6, the integral shoulder I84 on rod I04 will engage the lookout lever I80 and prevent reclosure of the circuit breaker contacts. It will be noted that pinion I30 is provided with a solid tooth portion I83 which, when rack I8I attempts to reclose the contacts a third successive time, will be moved to engage and cam rack I3I out of engagement with pinion I30, and thereby permit the'rack and solenoid core I20 to drop down under the influence of gravity and spring I23, to the position shown in Figs. 1 and 3. This will obviously permit spring I88 to reset gear I38 into engagement with the inclined end of lever I44. However, lockout lever I80 is maintained in the position shown in Fig. 4 to lock the contacts open by reason of its frictional engagement with shoulder I 84.

To reset the breaker, that is, to place it in service again following an automatic lockout operation, it is necessary to raise the moving contact in order to release lockout lever I80 and permit spring I18 to move the lever I44, and, consequently, lockout lever I80 away from rod I04 and thus release the movable contact and permit the same to be reclosed by toggle springs H6.

The movable contact may be manually lifted by means of a lever I 86 secured to a shaft I 81 extending transversely across the hollow portion of cover 32, with one end thereof extended outside of the hollow portion of the cover to have secured thereto an operating crank I80. The crank I has an enlarged aperture I82 at the outer end thereof, for the reception of a hook stick operating member or the like. It will be noted that operating crank lever I86 is provided with a curved inner end I88, positioned at one side of toggle levers H0 and beneath toggle pivot pin I08, so that although connecting rod I04 and movable contact I9 may be raised by lever I86 manually, it cannot be moved into engagement with the fixed contact 16 by this lever, and consequently it is obvious that the breaker contacts are trip free of manually operable lever I00 inasmuch as they may be automatically opened by the current responsive tripping means, independent of operation of the manual control lever As in the patent to H. L. Rawlim: et al., No.

aseaeoi ll porting rib Ill integral with the cover at the outside thereof (Figs. 2 and 5). Operating crank "I is provided with an integral stop shoulder Ill positioned so as to be engageable with locking lever Ill when the latter is manually rotated counterclockwise as viewed in Fig. 5, and when the operating crank is in its lower osition corresponding to the open circuit position of the contacts. The cover may also be provided with a sight glass I, as in the aforesaid copending application, for observation of a rod ill mounted on a float I88, to render the level of arc extinguishing fluid readily visible from the exterior of the interrupter. Likewise, the cover may embody a terminal III for connection of a circuit conductor thereto.

The electrical circuit through the breaker may be traced from the lower terminal ll, conducting strip II to bolt It, its enlarged head It, through coiled compression spring engageable between the enlarged head of bolt II and end cap ll of interrupter chamber 82. through fixed contact It and contact rod 18. The insulating contact rod support BI is provided with an oil center bore Ill for receiving a flexible conductor III, which is connected to contact rod II as at 2|, and this flexible conductor is directed upwardly to be connected to one end of solenoid coll Ill. The other end of solenoid coil III is connected by a flexible conductor 201. to the free end of bimetal I. and since the bimetal is supported on frame supporting plate 5|, the circuit from the bimetal through the frame to cap 32 and terminal I. It can be seen, as

previously referred to, that the coil I II and bimetal III are thereby arranged in series circuit relation so as to be effective to interrupt the circuit in the manner described above.

From the foregoing, it can be seen that the circuit breaker constituting this invention is capable of giving a relatively quick or an instantaneous trip when an overload first occurs on the circuit, and in the event the overload continues after automatic reclosure of the breaker contacts, a second time lag tripping will occur, and thereafter in the event the fault continues the subsequent tripping will be a quick or instantaneous one, and thereafter the breaker contacts will be locked in an open circuit position. It will also be noted that the time delay means operative to delay a reclosure of the breaker contacts is dependent upon the viscosity of the arc extinguishing fluid. so that the time delay in reclosing the breaker contacts will correspond to the time necessary for flushing the interrupting chamber so as to always insure a good flushing action and replacement of used are extinguishing liquid in the interrupting chamber 82, with fresh liquid. Another important feature is that this time delay in reclosure of the breaker contacts will be a constant value for any given viscosity of are extinguishing fluid, due to the fact that the time delay is controlled by movement of the solenoid core. rather than by movement of the contacts, and because of the lost motion between the core and movable contact, the movement of the core will always be suillcient to engage rack ill with the time delay reclosing means on each interrupting operation of the breaker. Also novel means have been disclosed for locking the breaker contacts in an open circuit position in response to a predetermined number of closely successive interrupting operations, but which will be inoperative to lock the breaker contacts i open irrespective of the number of non-successive interrupting operations of the breaker.

Having described a preferred embodiment of the invention in accordance with the patent statutes, it is desired that the invention be not limited to this particular embodiment inasmuch as it will be obvious particularly to persons skilled in the art that many modifications may be made in this particular structure and still remain within the scope of this invention.

We claim as our invention:

1. In a circuit interrupter, separable contacts. means for separating said contacts in response to a circuit condition to interrupt the circuit, said contacts being biased closed to automatically close the circuit after a circuit interrupting operation, an actuating member adapted to be advanced a predetermined amount during each separation and reclosure cycle of said contacts and to slowly return to a normal position, movably mounted spring biased means normally positioned to be engaged and moved by said member in response to predetermined advancement thereof to another position where it prevents reclosure of said contacts, manually operable means for rendering said reclosure preventing means inoperative, to thereby permit reclosure of said contacts, said manually operable means adapted to occupy one position when said contacts are closed and being movable to a second position to cause opening of said contacts, and said manually operable means being free of said contacts when at said one position so that said contacts may be separated by said electro-responsive means even when said manually operable means is held at said one position.

2. In an automatic circuit recloser. separable contacts, overload-responsive means for causing separation of said contacts to interrupt the circult, means for automatically reclosing said contacts after a circuit interrupting operation, normally inactive means adapted when activated to prevent reclosure of said contacts by said reclosing means, integrating means biased to a normal positionandadaptedtobeadvancedapredetermined amount on each circuit interrupting operation. said integrating means mounted for movement independent of said normally inactive means and arranged so that when advanced an amount greater than said predetermined amount by a plurality of closely successive circuit interrupting operations it will activate said reclosurepzeventing means. the return movement of said integrating means under the influence of its bias being independent of said reclosure preventing means. and manually operable means for causing resetting of said reclosure-preventing means.

3. In an automatic circuit reclcser, separable contacts, overload-responsive means for causing separation of said contacts to interrupt the circuit, means for automatically reclosing said contacts after a circuit interrupting operation, normally inactive means adapted when activated to prevent reclosure of said contacts by said reclosing means, integrating means responsive only to a predetermined number of closely successive circult interrupting operations to be advanced a predetermined amount, means positioned to be engaged by said integrating means only when advanced said predetermined amount to activate said reclosure-preventing means, and manually operable means mounted for movement independently of said integrating means for resetting said reclosure-preventing means.

Q, In a circuit interrupter, separable contacts.

means for separating said contacts in response to a predetermined circuit condition, means for automatically closing said contacts in response to a circuit interrupting operation, means for delaying closing movement of said contacts including an actuating member adapted to be advanced a predetermined amount by each operation of said reclosing means, movably mounted latch means normally occupying a released position for releasably holding said contacts separated when moved to latching position, and said latch means having a part positioned to be engaged by said actuating member after it has been advanced a predetermined amount to move said latch means to its latching position.

5. In a circuit interrupter, separable contacts, means for. separating said contacts in response to a predetermined circuit condition, means for automatically closing said contacts in response to a circuit interrupting operation, means for delaying closing movement of said contacts including an actuating member adapted to be advanced a predetermined amount by each operation of said reclosing means, normally inactive means for releasably holding said contacts separated when activated, said last mentioned means having a part positioned to be engaged by said actuating member after it has been advanced a predetermined amount to activate said holding means, and means for slowly returning said actuating member to its original position independent of said holding means, whereby said contact holding means is operative to maintain said contacts separated only in response to a predetermined number of closely successive circuit interrupting operations, and said actuating member will be reset while the contacts are maintained separated.

6. In a circuit interrupter, separable contacts, means for separating said contacts in response to a predetermined circuit condition, means for automatically closing said contacts in response to a circuit interrupting operation, means for delaying closing movement of said contacts including an actuating member, adapted to be advanced a predetermined amount by each operation of said reclosing means, movably mounted latch means normally occupying a released position for releasably holding said contacts separated when moved to latching position, said latch means having a part positioned to be engaged by said actuating member after it has been advanced a predetermined amount to move said latch means to its latching position, and manually operable means for releasing said latch means.

7. In a circuit interrupter, separable contacts, means for separating said contacts in response to a predetermined circuit condition, means for automatically closing said contacts in response to a circuit interrupting operation, means for delaying closing movement of said contacts including an actuating member adapted to be advanced a predetermined amount by each operation of said reclosing means, movably mounted latch means biased to a normal inoperative position for releasably holding said contacts separated when rendered operative, said latch means being positioned to be engaged by said actuating member after it has been advanced a predetermined amount to render said latch means operative, and manually operable means for actuating said contacts in a direction to release said latch means and permit the latter to resume its normal inoperative position under the influence of its bias.

8. In a circuit interrupter, separable contacts,

means for separating said contacts in response to a predetermined circuit condition, means for automatically closing said contacts in response to a circuit interrupting operation, means for delaying closing movement of said contacts including an actuating member adapted to be advanced a predetermined amount by each operation of said reclosing means, movably mounted latch means biased to a normal inoperative position for releasably holding said contacts separated when rendered operative, said latch means being positioned to'be engaged by said actuating member after it has been advanced a predetermined amountto render said latch means operative, manually operable means for actuating said contacts in a direction to release said latch means and permit the latter to resume its normal inoperative position under the influence of its bias, and means biasing said actuating member in a direction to reset independently of said latch means.

9. In a circuit interrupter, separable contacts, means for separating said contacts in response to a predetermined circuit condition, means for automatically closing said contacts in response to a circuit interrupting operation, means for delaying closing movement 01. said contacts including an actuating member adapted to be advanced a predetermined amount by each operation of said reclosing means, means having a movably mounted part positioned to be engaged by said actuating member after it has been advanced an amount greater than said predetermined amount to move said part to a position where reclosing of said contacts is prevented, and manually operable means for etfecting release movement of said reclosure-preventing means.

10. In a circuit interrupter, separable contacts, means for separating said contacts in response to a predetermined circuit condition, means for automatically closing said contacts in response to a circuit interrupting operation, means for delaying closing movement of said contacts including an actuating member adapted to be advanced a predetermined amount by each operation of said reclosing means, movably mounted means adapted at one position thereof to prevent reclosing of said contacts but normally at another position where it does not interfere with contact closing, said movably mounted means having a part positioned to be engaged by said actuating member only in response to advancement of the the latter an amount greater than said predetermined amount to move said movable means to its aforesaid one position and thus prevent reclosing or the contacts.

11. In a circuit interrupter, separable contacts, means having a part movable a predetermined amount from a normal position for separating said contacts in response to a, predetermined circuit condition, means for automatically closing said contacts in response to a circuit interrupting operation, means for delaying closing movement of said contacts including an actuating member adapted to be advanced a predetermined amount by each operation of said reclosing means, movably mounted latch means normally occupying a released position for releasably holding said contacts separated when moved to latching position, said latch means having a part positioned to be engaged by said actuating member after it has been advanced a predetermined amount to move said latch means to its latching position, manually operable means for releasing said latch means, stationary stop means separate from and independent of said contact means for defining the normal position of said part, and means for restoring said part to its normal position after a circuit interrupting operation.

12. An automatic reclosing circuit breaker comprising, separable butt-type contact means one of which is mounted on a slidable contact rod for movement into and out of engagement with the other, overload-responsive means having a part. slidably mounted on said rod and havin lost motion therewith so as to be movable a predetermined distance from a normal position in response to overloads before causing separation of said contacts, means for automatically closing said contacts in response to a circuit interrupting operation, means for delaying closing movement of said contacts including an actuating member adapted to be advanced a predetermined amount by each operation of said reclosing means, movably mounted latch means normally occupying a 20 2,275,885

released position for releasabiy holding said contacts separated when moved to latching position, said latch means having a part positioned to be REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,069,082 Walle Jan. 26, 1937 Bartlett Mar. 10, 1942 2,333,604 Wallace Nov. 2, 1943 2,352,048 Wallace June 20, 1944 

